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The European Union's Water Framework Directive (WFD) requires that all Member States within the European Union determine reference conditions for aquatic ecosystems to provide a baseline against which to measure the effects of past and present activities. Reference conditions are subsequently used to classify the ecological status of European waters. The decisions regarding environmental status will be important future elements in the management of European coastal waters. We have developed a number of classification scenarios for total nitrogen (TN) in the overlying waters of the southern part of Roskilde Fjord, Denmark, taking as our basis a palaeoecological reconstruction of fluctuations in TN between 1850 and 1995. We present a provisional classification scheme for the ecological status of Roskilde Fjord, sensu the WFD. Decision(s) regarding the deviation from reference conditions will give a wide range of apparent ecological status from good, through moderate and poor, to bad depending upon the definition of an acceptable deviation from reference conditions. The determination of an acceptable deviation will ultimately be a political decision, and will result in a wide range in the protection of coastal waters in Europe. There is still, however, an urgent need for a sound scientific documentation of the various scenarios for the implementation of the WFD.  相似文献   

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To answer the requirement of the European Commission's Water Framework Directive (WFD) for biological-effects endpoints to classify the ecological health of aquatic ecosystems, we propose the biomarker response index (BRI). The BRI, based on a suite of biomarkers at different levels of biological response at the individual level, provides an integrated relative measure of the general health status of coastal invertebrates. Using the BRI, the health of mussels (Mytilus edulis) from 10 estuaries classified by the Environment Agency of England and Wales under the WFD was compared. Eight sites were healthier than predicted and two showed a similar health status to that of the predicted point-source pollution risk classification. Results indicate that the BRI offers a potential measure of organism health that can be used in monitoring under the WFD as an additional aid to reduce uncertainty in defining risk classification and to provide better evidence of existing impact.  相似文献   

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The trophic status classification of coastal waters at the European scale requires the availability of harmonised indicators and procedures. The composite trophic status index (TRIX) provides useful metrics for the assessment of the trophic status of coastal waters. It was originally developed for Italian coastal waters and then applied in many European seas (Adriatic, Tyrrhenian, Baltic, Black and Northern seas). The TRIX index does not fulfil the classification procedure suggested by the WFD for two reasons: (a) it is based on an absolute trophic scale without any normalization to type-specific reference conditions; (b) it makes an ex ante aggregation of biological (Chl-a) and physico-chemical (oxygen, nutrients) quality elements, instead of an ex post integration of separate evaluations of biological and subsequent chemical quality elements. A revisitation of the TRIX index in the light of the European Water Framework Directive (WFD, 2000/60/EC) and new TRIX derived tools are presented in this paper. A number of Italian coastal sites were grouped into different types based on a thorough analysis of their hydro-morphological conditions, and type-specific reference sites were selected. Unscaled TRIX values (UNTRIX) for reference and impacted sites have been calculated and two alternative UNTRIX-based classification procedures are discussed. The proposed procedures, to be validated on a broader scale, provide users with simple tools that give an integrated view of nutrient enrichment and its effects on algal biomass (Chl-a) and on oxygen levels. This trophic evaluation along with phytoplankton indicator species and algal blooms contribute to the comprehensive assessment of phytoplankton, one of the biological quality elements in coastal waters.  相似文献   

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The European Water Framework Directive (WFD) establishes a framework for the protection and improvement of estuarine (transitional) and coastal waters, attempting to achieve good water status by 2015; this includes, within the assessment, biological and chemical elements. The European Commission has proposed a list of priority dangerous substances (including metals such as Cd, Hg, Ni and Pb), with the corresponding list of environmental quality standards (EQS), to assess chemical status, but only for waters. In this contribution, a long-term (1995–2007) dataset of transitional and coastal water and sediment trace elements concentrations, from the Basque Country (northern Spain), has been used to investigate the response of these systems to water treatment programmes. Moreover, the approach proposed in the WFD, for assessing water chemical status (the ‘one out, all out’ approach), is compared with the integration of water and sediment data, into a unique assessment. For this exercise, background levels are used as reference conditions, identifying the boundary between high and good chemical status. EQS are used as the boundary between good and moderate chemical status. This contribution reveals that the first approach can lead to misclassification, with the second approach representing the pattern shown by the long-term data trends. Finally, the management implications, using each approach are discussed.  相似文献   

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The European Water Framework Directive requires the development of new and accurate methodologies, addressing the assessment of the physico-chemical status of transitional and coastal waters; these are considered by the Directive as the supporting elements for the final evaluation of the Ecological Quality Status.

This contribution develops new approaches in the determination of the physico-chemical status, solving some problems detected in previous contributions, i.e.: (a) fitting the classification of water bodies and typologies, by means of the stretching of the typologies, according to the natural salinity gradient of types; (b) defining reference conditions, based upon the new approach to typologies, (c) proposing accurate multivariate methodologies, in determining the physico-chemical status of the transitional and coastal waters, based upon the defined typologies and references; and (d) discussion of the results obtained by reference to methodological aspects and water quality evolution in the Basque Country, Spain (as a case-study), during the last decade.  相似文献   


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The EU Water Framework Directive (WFD) requires the ecological assessment of water bodies. Since the littoral zones and the lakeshores are part of lakes as water bodies as defined by the WFD, a new scheme for ecological quality assessment of lakeshores should be established. It is proposed that this scheme should go beyond the formal requirements of the WFD, as it includes aspects of nature conservancy, landscape protection, and regional planning and development. Some of these aspects are subject to other EU legislation (e.g. Habitats Directive) and some are subject to national legislation. Ten general Quality Elements (QEs) are proposed, which can be refined and reified through several levels of detail, depending on the specific aims of a study. A list of eleven topics, which should be discussed in the establishment of the lakeshore quality assessment scheme, is given. The more complex ones are the implementation of other EU legislation, the definition of lakeshore types and reference conditions, the stipulation of best aggregation procedures, and a better understanding of the significance of hydrological and morphological impacts on the biota.  相似文献   

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This study presents the 26 major surface water types established in Austria in accordance with the draft of the EU Water Framework Directive (WFD). These types are made up of so‐called aquatic landscape units and large rivers. The 17 aquatic landscape units were defined using a database in which all Austrian running waters with a catchment area greater than 10 km[2] were described according to the following typological features: size of catchment area, altitude of catchment area and confluences, stream order, geology, zoogeographical regions (ecoregions), and subregions. At running waters with gauges, a classification according to flow regimes was carried out. Large rivers were defined as running waters with a stream order ⩾7 and/or a catchment area > 2500 km2 and/or with an average flow >50 m3/s. These major types represent, inter alia, the basis for the establishment of a surveillance monitoring network as required by the WFD.  相似文献   

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The European Union Water Framework Directive (WFD), a new regulation aiming to achieve and maintain a clean and well-managed water environment, refers to phytoplankton as one of the biological quality elements that should be regularly monitored, and upon which the reference conditions of water quality should be established. However, the use of phytoplankton as a biological quality element will result in several constraints, which are analyzed in this article with examples from Portuguese waters. Specifically, the establishment of reference conditions of water quality may be difficult in some water bodies for which no historical data exists. The sampling frequency proposed for phytoplankton monitoring does not seem suitable to assess phytoplankton succession, and may preclude the detection of algal blooms. Finally, the use of chlorophyll a as a proxy of phytoplankton biomass and abundance has been proposed by some authors, but it may overlook blooms of pico- and small nanophytoplankton, and overestimate the importance of large microphytoplankton. Furthermore, most studies in Portugal have used only inverted microscopy for phytoplankton observation and quantification; this method does not permit the distinction between autotrophic and heterotrophic cells, especially in samples preserved with Lugol's solution, and does not allow the observation of smaller-sized cells. Finally, some techniques, such as remote sensing and chemotaxonomic analysis, are proposed to be used as supplements in phytoplankton monitoring programs.  相似文献   

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The European Water Framework Directive (WFD) establishes a framework for the protection and improvement of transitional and coastal waters; its final objective is to achieve at least 'good water status' for all waters, by 2015. The WFD requires Member States (MSs) to assess the Ecological Status (ES) of water bodies. This assessment will be based upon the status of the biological, hydromorphological and physico-chemical quality elements, by comparing data obtained from monitoring networks to reference (undisturbed) conditions, and then deriving an Ecological Quality Ratio (EQR). One of the biological quality elements to be considered is the benthic invertebrate component and some structural parameters (composition, diversity and disturbance-sensitive taxa) must be included in the ES assessment. Following these criteria, several approaches to benthic invertebrate assessment have been proposed by MSs. The WFD requires that these approaches are intercalibrated. This contribution describes the comparison of the different methodologies proposed by United Kingdom, Spain, Denmark and Norway. Results show a high consistency between the approaches, both with regard to determining the EQR and boundary settings for the ES.  相似文献   

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This paper describes the hydrochemistry of a lowland, urbanised river‐system, The Cut in England, using in situ sub‐daily sampling. The Cut receives effluent discharges from four major sewage treatment works serving around 190 000 people. These discharges consist largely of treated water, originally abstracted from the River Thames and returned via the water supply network, substantially increasing the natural flow. The hourly water quality data were supplemented by weekly manual sampling with laboratory analysis to check the hourly data and measure further determinands. Mean phosphorus and nitrate concentrations were very high, breaching standards set by EU legislation. Although 56% of the catchment area is agricultural, the hydrochemical dynamics were significantly impacted by effluent discharges which accounted for approximately 50% of the annual P catchment input loads and, on average, 59% of river flow at the monitoring point. Diurnal dissolved oxygen data demonstrated high in‐stream productivity. From a comparison of high frequency and conventional monitoring data, it is inferred that much of the primary production was dominated by benthic algae, largely diatoms. Despite the high productivity and nutrient concentrations, the river water did not become anoxic, and major phytoplankton blooms were not observed. The strong diurnal and annual variation observed showed that assessments of water quality made under the Water Framework Directive (WFD) are sensitive to the time and season of sampling. It is recommended that specific sampling time windows be specified for each determinand, and that WFD targets should be applied in combination to help identify periods of greatest ecological risk. © 2015 The Authors. Hydrological Processes published by John Wiley & Sons Ltd.  相似文献   

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The assessment of estuaries based on benthic communities is widely used to determine impacts caused by human pressure and is one of the required tools for the implementation of the European Water Framework Directive (WFD). Our study compared multimetric approaches (B-IBI and TICOR) to assess the benthic condition of three Portuguese estuaries (Mondego, Tejo, and Mira rivers) with different levels of natural and human induced stress. Benthic community condition was classified into quality status categories of the WFD and compared for consistency with a priori status categories based upon physical-chemical criteria. Both multimetric indices discriminated equally well between locations classified above or below the good status category but were unable to provide good separation between other quality classes (high/good, moderate, poor/bad). Metrics included in these indices are greatly affected by natural stress and we recommend the development of habitat-specific thresholds to increase the discriminatory ability of any benthic condition index.  相似文献   

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In the last decade a politically inspired marine protection movement arose in the European Union. This movement leads to an holistic strategy. Merging the Water Framework Directive (WFD) and the Marine Strategy Directive (MSD) along the European coastline demands sophisticated ecological classification procedures. The ‘Benthic Quality Index’ (BQI) is one of several indices created in view of the WFD. We used the dynamic species reference system ES500.05 to test the capability of BQI to exclude primary environmental factors including the salinity gradient and depth (a proxy for the oxygen regime) from the ecological quality (EcoQ) assessment.A macrozoobenthos dataset of the southern Baltic Sea spreading over more than 20 years and over 100,000 km2 was used for the EcoQ assessment. Quality assurance rules were applied to the record set and an analytical dataset of 936 sampling events with 20,451 abundance records was used in the analysis. We show that the natural salinity gradient has a severe impact on the BQI based EcoQ. We adapted the calculation procedure to reduce the salinity effects to a minimum.According to the adaptation 503 sensitivity/tolerance values for 87 species were computed. These values were calculated within seven salinity ranges from 0 to >30 PSU and two depth zones. These values can be used as a reference for further investigation in the Baltic and other areas with similar environmental conditions.  相似文献   

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Mining dumps are major sources of pollutants within the mining area of Lausitz, especially sulphate and iron. Their existence in catchment areas comprising groundwater bodies or lakes often imposes negative effects on the water quality. The European Union Water Framework Directive [EU-WFD, 2000. Directive 2000/60/EC of the European Parliament and of the Council of 23 October 2000 establishing a framework for Community action in the field of water policy. The European Parliament and Council, L327/1, p. 72] aims to achieve ‘good quality’ status for all water bodies across Europe by 2015. Consequently, predicting the development of ground and lake water quality is necessary and must be based on the geochemical composition of the mining dumps. Therefore, the dumps need to be quantified as pollutant sources.A method to calculate the amount of sulphate in mine dumps is presented. It is based on historic geological and geochemical data characterising the pre-mining situation. Additional information on the dump body, derived from the vertical extension of mining activities and the current Digital Elevation Model (DEM), allows the composition of the dump to be determined. This procedure is demonstrated for the Bärwalde site. An average total sulphur content of 0.62% (5.9 million tonnes) was calculated for the Bärwalde dump. About 40% of it is estimated to be pyrite sulphur. Applying an average pyrite oxidation rate for the whole dump body of 7% led to an additional water-soluble mass of 0.18 million tonnes of sulphate sulphur.Applying this technique to all mine dumps managed by the postmining administration company LMBV, will improve our knowledge of the catchment area for the different lakes of Lausitz and will form an essential basis for reactive transport calculations.  相似文献   

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Fluvial geomorphology is rapidly becoming centrally involved in practical applications to support the agenda of sustainable river basin management. In the UK its principal contributions to date have primarily been in flood risk management and river restoration. There is a new impetus: the European Union's Water Framework and Habitats Directives require all rivers to be considered in terms of their ecological quality, defined partly in terms of ‘hydromorphology’. This paper focuses on the problematic definition of ‘natural’ hydromorphological quality for rivers, the assessment of departures from it, and the ecologically driven strategies for restoration that must be delivered by regulators under the EU Water Framework Directive (WFD). The Habitats Directive contains similar concepts under different labels. Currently available definitions of ‘natural’ or ‘reference’ conditions derive largely from a concept of ‘damage’, principally to channel morphology. Such definitions may, however, be too static to form sustainable strategies for management and regulation, but attract public support. Interdisciplinary knowledge remains scant; yet such knowledge is needed at a range of scales from catchment to microhabitat. The most important contribution of the interdisciplinary R&D effort needed to supply management tools to regulators of the WFD and Habitats regulations is to interpret the physical habitat contribution to biodiversity conservation, in terms of ‘good ecological quality’ in rivers, and the ‘hydromorphological’ component of this quality. Contributions from ‘indigenous knowledge’, through public participation, are important but often understated in this effort to drive the ‘fluvial hydrosystem’ back to spontaneous, affordable, sustainable self‐regulation. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

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Macroalgae is a biological key element for the assessment of the ecological status in coastal waters in the frame of the European Water Framework Directive (WFD, 2000/60/EC). Here we propose a methodology for monitoring water quality based on the cartography of littoral and upper-sublittoral rocky-shore communities (CARLIT, in short). With the use of spatial databases, GIS, and available information about the value of rocky-shore communities as indicators of water quality, it is possible to obtain an environmental quality index representative of the ecological status of rocky coasts. This index, which completely fulfils the requirements of the WFD, is expressed as a ratio between the observed values in the sector of shore that is being assessed and the expected value in a reference condition zone with the same substrate and coastal morphology (Ecological Quality Ratio, EQR). The application of this index to the coast of Catalonia (North-Western Mediterranean) is presented.  相似文献   

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